Raytheon Missile Systems Division (MSD) is a division of the Raytheon Corporation's Electronics segment. Headquartered in Bedford, Massachusetts, Raytheon MSD also has additional sites in Andover, Lowell, and Tewksbury, Massachusetts, as well as Bristol Tennessee. These sites cover more than 3,000,000 square feet and house over 16,000 employees. The MSD product line includes many foremost missile systems currently in use by the U.S. Armed Forces and international customers. These systems include the Patriot and Hawk Air-Defense Systems, Stinger Surface-to-Air Missile, Standard Missile-2, Sparrow Missile, Sidewinder Missile and Advanced Medium Range Air-to-Air Missile.